The present invention relates to a disc-like recording medium such as floppy disc, a disc drive and a method of reading information signal recorded in the disc-like recording medium.
Recently, increasingly more attention has been paid to an increased density recording of information in a removable disc-like recording medium such as floppy disc and the like. To this end, a large capacity floppy disc of several tens megabytes, for example, has been proposed.
If the removable disc-like recording medium of this type is changed in format in a same form as in the existing recording medium or a next generation standard is proposed for the recording medium, a recording apparatus and reproducing apparatus have to identify the format of the medium and a standard applied therein. Generally, for the format and standard identification, an identification hole or the like, for example, is provided in the envelope encasing the disc-like recording medium.
However, floppy discs as a typical example of the above-mentioned removable recording medium already include some versions and many types of large capacity floppy discs will be proposed as next generation floppy discs to support a future high density recording. Therefore, to identify floppy discs of a next generation and a further generation, corresponding identification holes or cuts have to be formed in the envelopes of the respective floppy discs.
Practically, however, so many identification holes or cuts as the kinds of floppy discs could not unlimitedly be formed in the floppy disc envelopes. Also, recording/reproducing apparatus could not be provided with detectors to identify the identification holes or cuts formed in the floppy disc envelope for identification of such holes or cuts in the floppy disc envelope.
Accordingly, the present invention has an object to overcome the drawbacks of the prior art by providing a disc-like recording medium, a disc drive and a method of reading the disc-like recording medium, adapted to identify the write format and the like provided on the medium without the necessity of any extra identification holes or cuts formed in the envelope for the recording medium and additional detectors provided in the recording/reproducing apparatus as well as with only a minimum necessary increase of the load to the hardware.
The above object can be achieved by providing a disc-like recording medium with a plurality of substantially circumferential tracks, having formed thereon a plurality of servo areas in which tracking servo information is recorded and a plurality of data areas, the servo and data areas being disposed alternately in each of the tracks, one servo area in each track and a data area following the servo area forming together one servo frame, an format information being recorded along with the servo information in the servo area.
The plurality of tracks includes a plurality of user data tracks and an empty track formed along at least either of the outermost and innermost circumferences of the disc-like recording medium, the format information being recorded in the servo area on the empty track.
The above object can also be achieved by providing a disc drive adapted to drive and read a disc-like recording medium with a plurality of substantially circumferential tracks, having formed thereon a plurality of servo areas in which tracking servo information is recorded and a plurality of data areas, the servo and data areas being disposed alternately in each of the tracks, one servo area in each track and a data area following the servo area forming together one servo frame, an format information being recorded along with the servo information in the servo area, comprising:
a head to read information recorded in the disc-like recording medium;
means for moving the read head radially of the disc-like recording medium;
means for generating a tracking servo signal based on an output of the read head; and
means for controlling the read head to read the servo information from any one of the servo areas, the moving means to seek the read head to the empty track, and the read head to read the format information of the empty track.
Further the above object can be achieved by providing a method of reading a disc-like recording medium with a plurality of substantially circumferential tracks, having formed thereon a plurality of servo areas in which tracking servo information is recorded and a plurality of data areas, the servo and data areas being disposed alternately in each of the tracks, one servo area in each track and a data area following the servo area forming together one servo frame, an format information being recorded along with the servo information in the servo area, comprising the steps of:
reading the servo information from any one of the servo areas;
allowing a read head to seek the empty track based on the read servo information; and
reading the format information of the empty track.